Conventionally, an image forming apparatus such as a Multi Function Peripheral (MFP) is used to form an image on a sheet (paper). For enabling the reuse of the sheet by erasing an image formed on the sheet, there exists a technique where an image is printed on the sheet using a coloring agent having a decoloring property, such as ink containing a leuco dye.
A coloring agent having decoloring property is erased when the coloring agent is subjected to a high temperature. Accordingly, to reuse a sheet, the sheet is heated using an erasing device, thus erasing an image formed on the sheet. The erasing of an image formed on a sheet may be referred to as “decoloring” in the explanation made hereinafter.
In the erasing device, a platen roller and a heat source are arranged in an opposed manner with a sheet conveyance path interposed between the platen roller and the heat source. The sheet is heated by conveying the sheet between the platen roller and the heat source, thus erasing a coloring agent having decoloring property. A cooling fan for cooling the device is mounted downstream of the platen roller and the heat source. Accordingly, the sheet which is conveyed along a conveyance guide is cooled by air from the cooling fan.
However, when the sheet conveyance path includes a curve, the sheet is pressed to an outer side of the curve thus giving rise to a drawback that a jam is liable to occur. Although this drawback may be overcome by increasing a radius of the curve, there arises a drawback that the device becomes large-sized.